Spark-plug



M. GOTTLIEB.

SPARK PLUG. APPLICATION FILED FEB. 10, 1919.

1,374,847. Patented Apr. 12,1921.

I W "I t\ 3 1 11 WITNESS: INVENTOR.

r 1mm 00/11/24 BY A TTORNE Y.

UNITED STATES MORRIS GOT'ILIEB, OF PHILADELPHIA, PENNSYLVANIA.

SPARK-PLUG.

Specification of Letters Patent.

Patented Apr. 12, 1921 Application filed February 10, 1919. Serial No. 276,064.

V T 0 all whom it may concern:

Be it known that I, Monms GoT'rLrEB, a citizen of the United States, residing at 2644 South 8th street, Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented new and useful Improvements in Spark-Plugs, of which the following is a specification.

The invention relates to spark plugs and has for an object to provide a spark plug for use in exploding the gas or gases-particularly in connection with the combustible gas in an internal combustion motor, and in which the electrodes of the spark plug will be protected to prevent undue accumulation ofcarbon deposit or oil, thereby increasing the value and intensity of the spark produced.

Among other features, the invention. comprehends the provision of a sparkplug, which can be cheaply manufactured and which consists of few and simple parts that can be readily assembled, the main feature however, comprising a conical hood or cover for the open end of the jacket, which hood or cover forms the groundelectrode, theconical configuration of the cover whereby the side wall thereof will be inclined, preventing any accumulation of oil at the apex of the conical cover and which apex forms oris a part of the ground electrode.

In the further disclosure of the invention, reference is to be had to the accompanying drawings, constituting a part of this specification in which similar characters of reference, denote corresponding parts in all the views, and in which,-

Figure 1 is a vertical sectional taken through the spark plug Fig. 2- is a bottom plan view, and

view

Fig. 3- is a fragmentary vertical sectional view of a slightly modified form,

Referring more particularly to the views, the numeral '10 indicates a jacket which may be suitably threaded as at 11, and has disposed therein a porcelain holder 12, carrying a main electrode 13, which passes through the holder and is insulated from the jacket thereby, said electrode 13 having a projecting end 14, adjacent the lower end of the jacket, with a suitable nut 15 threaded into the jacket to secure the porcelain holder rigidly in place:

The lower or open end of the jacket 10 is closed by a cover or hood 16, and attention particularly called to the configuration of the hood, namely that it is of a conical formation. The hood along its peripheral edge may be secured in any desired manner,

to the lower extremity of the jacket, and by reason of 1ts conical formation, it extends upwardly 1n the jacket to apoint adjacent the projecting end of the main electrode 13.

will form an a ex, it will be noted that at this point the mod is slightly indented to form an upwardly projecting tit indicated by the numeral 19, and this formation, it will be seen conforms to the configuration of the side-wall of the hood or cover, so-that any oil or other deposits on the ground electrode or apex, will be drained therefrom by the conical configuration of the hood and will pass out through the apertures 17 In Fig. 3, it will be seen that I provide a slightly modified form, wherein instead of having the tit 19 formedintegral with the hood or cover, I make the same in a separate piece, indicated-by the numeral 20, provided with a threaded stem 21, threaded through an opening 22 in the apex of the hood or cover with a plurality of locking nuts 23 threaded onto the stem to secure the tit 20 in rigid position. It will :be seen that with this construction the tit or ground electrode can be readily adjusted to be brought closer to or farther away from the projecting end of the main electrode 13.

I am aware that various forms of spark plu s have been used heretofore, which comprehend inclosing the lower part of the jacket for. the purpose of preventing the accumulation of oil or carbon on an electrode, and I am also aware of various forms of attachments that have been used in an endeavor to accomplish this purpose. I have found however, from actual experience, that with a construction such as I have set forth, I obtain what might be termed a self-draining spark plug, 111 that the ground or secondary electrode will be kept substantially free from carbon or oil deposits already received, by the conical formation thereof and which, on account of the steep angularity of the wall, causes the carbon or oil deposit to be drained or jarred from the contact point in the use of the lug.

Still further it will be seen that any oil ,-will drain down the outside, of the cover so as to keep the contact point clean, and thus permit of obtaining a hot and intense spark.

I wish it to be understood that I do not claim to be the first person to inclose the open end of the jacket of a spark plug, but I have found that the ordinary closures generally employed are not sufficient to accomplish the purpose and that it is necessary to provide a construction whereby the lower electrode will be of an upstanding nature, and of a conical or pyramidal shape so as to form draining surfaces from the apex thereof.

Having claim,-

A spark plug comprising an outer metallic body, a body of insulation within said metallic body, an electrode extending centrally through said body of insulation and terminating considerably short of the end of the metallic body, a frusto-conic al metallic shell secured to and extending into the open .end of the metallic body and having its smaller end closed and formed With a threaded hole and having its peripheral wall apertured, a conical electrode point disposed upon the small end of said frustoconical shell and canying a threaded stem screwed into saidhole whereby the conical electrode point may be adjusted toward or from the end of said first named electrode, and lock nuts on said stem within the-frustoconical shell whereby to lock the conical point in adjusted position.

In testimony whereof I afiix my signature.

MORRIS GOTTLIEB.

described my invention, I 

